Am I mad? Mystery stem files

TreverT · Post by **TreverT** » Fri Jun 22, 2007 12:10 pm

OK, I seem to be losing my remaining marbles. I'm on a quick tool & supply buying lark, and I have the memory that I read here a thread about a thin hand file that was ideal for making bit slot interiors, because the files were long, could file deep, and only cut in ONE direction - i.e., you push it in and it cuts on the pullback, so it was easy and quick to gradually shave out a nice V without the risks of cutting it with a Dremel.

However, on searching, I can find no thread like this. Did I imagine it?

achduliebe · Post by **achduliebe** » Fri Jun 22, 2007 12:58 pm

Trever,

You are not mad at all. Look in the Stem Work section almost at the bottom. I believe the last post to the thread was April 30, 2006. The author of the thread was custom300 and the title of the thread was 'Buttons ---HELP!!!'.

The first posted reply has a picture of the broachs as they are called.

I think this is what you are talking about.

TreverT · Post by **TreverT** » Fri Jun 22, 2007 3:01 pm

That be them! Thank you much, kind sir. I just ordered a pair of the things in hopes they'll help with several different needs of mine.

achduliebe · Post by **achduliebe** » Fri Jun 22, 2007 3:39 pm

Glad to help!

munkey · Post by **munkey** » Fri Jun 22, 2007 5:08 pm

Link to post

kbadkar · Post by **kbadkar** » Wed Jun 27, 2007 11:59 am

I got those mini-broaches a while ago and they work fantastic... much better and more precise than the drill bit smearing for v-slotting the button. Yet, there is room for improvement, like I wish they'd go deeper so it could widen the round opening at the bottom of the v-slot and make it a bit rectangular. I find the pipe cleaner 'hangs' in the transition between the slot and the tapered drill hole. Has anyone tried a keyway broach? Here's a link to Enco's 1/16" keyway broach.

http://www.use-enco.com/CGI/INSRIT?PART ... A=395-1004

I think it might keep the slot nice and straight too? Any opinions before I shell out 20 bucks?

Nick · Post by **Nick** » Fri Jun 29, 2007 8:31 am

I actually use a scroll saw blade snipped in half. It cuts a great thin slot. It only cuts on the one side. And I can widen the slot out with a drill bit with ease.

bluesmk · Post by **bluesmk** » Fri Jun 29, 2007 8:35 am

Trever,
You're gonna love 'em. I've been using them for a few years now....wouldn't be without them !
Dan
Gabrieli Pipes

hazmat · Post by **hazmat** » Fri Jun 29, 2007 9:51 am

I ordered a set of these a coupla days ago. Can't wait till they show up so I can give them a try. The spinning drill bit method scares the bejeezus out of me, though I'm going to try to get a handle on it at some point. Till then, these little guys should do, based on the good comments I've read here in their regard.

kbadkar · Post by **kbadkar** » Fri Jun 29, 2007 12:21 pm

Hey Nick, brilliant idea about the scroll saw blade... now, why didn't I think of that?! I also have pull stroke jigsaw blades about 1/16" thick. I'll give them a try before experimenting with 20 bucks and a keyway broach.

TreverT · Post by **TreverT** » Fri Jun 29, 2007 1:09 pm

Someday I should post photos of the tool I use. I just took a blade pack for a hand saw and ground parts of the blades down to long thin V shapes that cut on one side. I've got the blade mounted in a hand wooden grip so it's essentially a 4" long micro-cutter.

This made no sense. I will take a pic next time I am shooting photos.

Leus · Post by **Leus** » Fri Jun 29, 2007 4:13 pm

That scroll saw idea is so brilliantly simple it makes me want to smack my head... that's why I love this forum.

Cheers,

Frank · Post by **Frank** » Sun Jul 01, 2007 4:58 am

A jigsaw blade ground down to a narrow taper, as Trever suggested, sounds like a good idea. I'll give it a try.

hazmat · Post by **hazmat** » Tue Jul 03, 2007 8:43 am

I received my broaches over the weekend. Is NIIIIIIIICE!!!! Work like a charm.

kbadkar · Post by **kbadkar** » Tue Jul 03, 2007 12:02 pm

I just stuck a jigsaw scroll saw blade on a wood file handle and ground down the tip to a nice thin taper. It did a brilliant job of rectangulating the transition point between the round tapered drill hole to the flat v-slot. Now a fluffy pipe cleaner passes with ease. Thanks guys!

LatakiaLover · Post by **LatakiaLover** » Sun Sep 30, 2007 12:51 am

Just cruising older threads, and came across this one. I do a lot of airway "flare cutting" so thought I'd add to the info-pot:

Drill bits pushed sideways try to move at right angles to the direction they're pushed, from friction, like a tiny wheel, so can keyhole the slot if not controlled precisely. That they aren't completely rigid also raises the "spookiness factor" of using them. On Lucite, they'll tend to melt material instead of cut it, too.

Saw blades of any kind have teeth bent out slightly wider than the blade they're part of (it's called "set") to keep the blade from binding in the work. Great for lumber, not so good for airways. Again, they can lead to keyholes, and the surface they leave is neither smooth or rounded, but rough and square-cornered.

A jeweler's broach files can do a good job, but they're tedious. A slow, iterative sort of application is necessary because their thickness doesn't match the slot being cut.

Best by far is a flat file of exactly the same thickness as the slot, wide enought it can't go sideways, smooth everywhere except for a half-round edge, and which cuts in both directions. Not only is the quality of the result superior, their use is (essentially) foolproof, and they can do the job in 60 seconds.

Such a thing is a production item, and available in guaged thicknesses. It's called a "Nut Slotting" file. They're used in the making of stringed instruments.

All that's necessary to make an airway "V-tool" from one is grind a "finger" on one end, so it will reach into the slot. Wrap the remaining fat part heavily with coach's tape (the kind gymnasts use---the adhesive won't migrate and make things sticky after heavy use), and you're set.

Here's the only source of decent quality ones I know of:

http://www.stewmac.com/shop/Tools/Files ... Files.html

TreverT · Post by **TreverT** » Sun Sep 30, 2007 8:58 am

But if you're grinding the tip of the thing to a wedge shape, you're grinding off the cutting sides. How does it cut from side to side?

JHowell · Post by **JHowell** » Sun Sep 30, 2007 11:20 am

It's always fascinating to see how a tool one maker considers an advantage another considers merely adequate, if not an actual disadvantage. In my experience, the set in a saw blade is not a problem at all -- a blade is set as much to one side as the other, so no "keyholing" occurs and the cut is straight. A saw blade is far more aggessive than any file, and if a thinner cut is desired, grinding off a bit of the set should suffice, though I find the width of the blades I use to be perfect. Duh, I guess that's why I use them. I never could get on with drill bits, either, but lots of makers who have been making pipes a lot longer than I have make some great pipes use them.

I have a set of nut files, and they were quite expensive and very fine in cut. The StewMac link didn't load for me, but I would guess they're still not cheap. And, being files, they will be brittle and more fragile than a saw blade when thinned to the dimension necessary to work into the airway. I've used lots of different things, including files, for funneling the slot. If you really want to use a file, it is cheaper and IMO more effective to get the coarsest and smallest rattail file available and grind down two opposite sides so you have two narrow, rounded cutting edges. Having access to a surface grinder helps. This modified file works pretty well, but not as well as the saw blades. Not to argue with or disparage anyone's choice of tools, but in my opinion it would be a disservice to discourage another maker from trying saw blades. They've been a huge timesaver for me.

It may be that Latakialover has tried saw blades and come to the opposite conclusion. Like I said, fascinating. OK, interesting.

LatakiaLover · Post by **LatakiaLover** » Sun Sep 30, 2007 1:02 pm

JH,

I just realized that eveyone's experience---and therefore their preferences and recommendations---is based on the individual specimens of tools they have used, not the class.

Duh. (slaps forehead)

Saws have all sorts of tooth types and counts, blade flex, and so forth, for example---and though I can imagine the perfect one for cutting airway V's, I've never found it for sale. Ditto files.

We'd all have to be able to share our experiences Spock Mind Meld style---or swap them through the mail in a weeks-long box pass of tools---to know exactly what went right and wrong while using them, too.

It just goes with the territory of being forced to use home-brewed, improvised stuff.

Re-reading my previous post with that in mind, I definitely sound too declarative. Anything that anyone has found to work is a valid candidate to try. My apologies. (I can see how a ground-flat-on-two-sides rat tail file could work well, for example, I just never tried one.)

TT,

The resulting shape isn't symmetrical, with the "finger" extending from the middle of the blade, but rather from one edge. Grind a 40-ish degree angle from one side almost to the other to make a near-point, then round the tip a little and relieve the last 5/8" or so with a concave curve.

JHowell · Post by **JHowell** » Mon Oct 01, 2007 1:34 am

Hi, LL,

If the photo of Trever's tool is still up, that's basically what I use -- mine are Bosch but almost any brand of bimetal 32 TPI blade would work, I think. The set is of the "wave" type, final cut is about .050-.060". I tried 24 TPI also and it works fine, but it's a little more grabby to start, can't be narrowed quite as much as the 32 because the teeth are just that tiny bit taller, and it removes material almost *too* fast.